


The Demon Who Eats Mysteries

by WingsOfTheDamned



Category: Kuroshitsuji | Black Butler, Majin Tantei Nougami Neuro
Genre: Demon Deals, Demons, Established Relationship, How Do I Tag, I Can't Believe I Wrote This, I Don't Even Know, I Will Go Down With This Ship, I Wrote This Instead of Sleeping, M/M, Mates, Other Additional Tags to Be Added, Pictures, Relationship Reveal, Some Humor, Teasing
Language: English
Status: Completed
Published: 2020-10-31
Updated: 2020-10-31
Packaged: 2021-03-09 00:55:22
Rating: General Audiences
Warnings: No Archive Warnings Apply
Chapters: 1
Words: 3,880
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/27296011
Author URL: https://archiveofourown.org/users/WingsOfTheDamned/pseuds/WingsOfTheDamned
Summary: Ciel finally managed to get another picture from Sebastian and this time he made sure to keep both Pluto and the demon himself outside the manor to see the results, glad to say he isn't disappointed by the results.
Relationships: Sebastian Michaelis/Nougami Neuro
Comments: 6
Kudos: 16





	The Demon Who Eats Mysteries

Ciel felt...

Proud.

Overjoyed even.

Because he won.

Because after a nightmare of a week he managed to get it.

A picture from Sebastian.

From that damn sneaky bastard.

He finally got it, and this time he had made sure to order the bastard to stay away from the manor for the next half hour and to keep Pluto out too.

Never be said Ciel Phantomhive gave up so easy.

A light knock at the door yanked him out of his thoughts.

-Come in.- He conceded, a smirk already playing at the corner of his lips as Bard stepped into his studio, Finny and Meyrin following right behind, their faces telling him something good had definitely come from all this ordeal.

-Young master... uh, we got it, here.- States Bard a bit awkwardly as he places the picture on the boy's hand, to be honest? Bard had a feeling a catastrophe was near, he just knew it, and the only survivor would be their young curious Lord.

-Thank you, you may take the rest of the day off, you did well this week.- Dismissed Ciel, the three servants were quick to bow at his words, nodding eagerly before leaving the studio, closing the door behind them.

-Who do you think that may be?- Wonders Finny as he remembers the man in the picture, he didn't look like he could be related to Mr.Sebastian, even if they shared the same weird vibe they didn't look alike at all.

-A friend probably.- Huffs Bard as he starts walking.

-Or a lover!- Proclaims Meyrin dreamy, a light nosebleed taking place on her face, Bard facepalmed at her words while Finny gasped in surprise.

-You think?- Asks Finny like he is actually considering her words.

-Of course the bastard hasn't a lover, that guy is definitely the type of guy who jumps from one woman to another.- Snorts Bard.

Ciel for his side can't do anything but stare at the picture on his hand, fingers tapping on the desk in an absent gesture, the guy in the picture was definitely not human.

Those eyes said it all.

That smile.

They held the same liar air, a facade to slap on for humans to see, Ciel wasn't stupid, he hadn't spent two years around a demon to not know when he had one infront of him.

But who was this?

The camera was suppose to show the dearest thing you held that no longer belonged to this world.

Was this person the dearest thing to Sebastian out of this world?

He had kind of believed it to be something more... impacting with that of the guy going as far as ordering Pluto to set fire to the prior thing.

He didn't knew for how long was he staring at the picture, all he knows is that another knock at the door pulled him out of his daydreaming.

-Young master I bring your tea.- Announced Sebastian looking as casual as always as he pushed the small cart inside, closing the door behind him.

-Forget about the tea who is this.- Demands Ciel showing the picture for more emphasis, Sebastian just tilted his head to the side and smiled.

-You don't want tea? Are you feeling quite alright young master?- Asks the demon completely ignoring the boy's question, Ciel scowls at that.

-Don't evade the question, I order you to tell me who is this.- Orders Ciel sharply, demons weren't suppose to have feelings, even Sebastian himself said it once, they didn't had feelings, then why was another demon in the picture? He didn't understand and he hated not understanding.

Sebastian for his side felt his eyebrow twitch at the kid's order, feeling the seal of the contract heaten up against the back of his hand, a tight feeling swirling inside his chest, warning as always of the punishment he would get if he was to go against his master's orders, he pressed his hand against his chest, bowing.

-As you wish my Lord, that demon is... my mate.

Ciel blinks at that, utterly caught off guard by those words.

-Mate? As in a lover kind of term?- Ciel found himself asking, feeling rather dumb as it was.

-Boyfriend, partner, husband, lover, whichever term feels better for you to use.- States the demon in a carefree manner, still smiling.

-You said demons had no feelings, that that was a human trait.- Accuses the boy sharply, the idea of the demon having the nerve to lie to him making his blood boil, a pang of what he refused to acknowledge as betrayal stinging inside his chest.

-Indeed my Lord I did said that and I wasn't lying, demons posses no feelings, but there are two types of demons in hell, those who feed from souls and those who feed from mysteries, it's only logical for us to attract each other due our nature, we make mysteries and they rot humans' souls when they yank the mysteries out, it's a win win from both sides.

-That doesn't explain why is he your dearest thing.- States Ciel matter of fact choosing to archive that information for later thoughts.

-Demons hate each other, it's in our nature, but since they don't like the same as us they don't come off as a threat, like I said, they rot souls, who wouldn't like someone who makes your food taste better? It's common nature I believe.- Says the demon like he is talking to a toddler, Ciel's eyebrow twitch at the tone.

-So you love him?

-No, that's quite the strong word, more like appreciate.- Corrects Sebastian matter of fact at the boy's question, he didn't felt love nor any kind of feelings in general, demons only held relationships based on interests, Neuro just happened to be the best at it, the terror he implanted in people at the last second, it made souls wield a different magnificent taste.

-I want to see him.- Declares Ciel after a moment, voice firm with decision, because he didn't want to risk not knowing everything about his butler, plus, there was a spark in him of curiosity, for what he knew Sebastian had said there were no other demons in the whole United Kingdom, and he was curious to know how a demon who ate mysteries worked.

Sebastian for his side made a face at the request.

-With all due respect I don't think that's a good idea my Lord.

-Why not?

-I just don't think it's prudent.- States the demon, he didn't want Neuro around Ciel, the boy's soul was... exquisite as it was, he didn't need him pulling strings to bring the mysterious kid's rot out into the shape of a monster, if he ate this mystery Sebastian's perfect meal would definitely dull out after he had busted his ass to perfection it at his taste.

-I don't care, I want to meet him,it's an order.- Demands the boy firmly, Sebastian's bites his tongue as he bows.

-Yes, my Lord.

~

-Oh the mysteries here are huge.- States Neuro as his eyes settle on the manor, taking a deep breath as he feels his skin bristle in excitement, this manor wielded more than one mystery, all of them so strong, so mouth watering, but there was one stronger than the others...

Yet he doesn't get to enjoy it for too long before a hand grasps the neck of his shirt, ruby eyes staring sharply at him.

-If you lay one single inch of your peak near any of those humans I will rip your tongue out.- Snaps Sebastian sharply, nose almost touching with the other's, Neuro smiles, sharp glowing green eyes staring back, challenging.

-I would love to see you try crow.- Red eyes glow even more sharper making Neuro snicker as he leans forward, cutting the distance between them to give the other a playful peck before leaning back raising a hand to his chest.- Won't touch them, it's bad manners to touch someone's food without their consent.

Sebastian releases him at that before sighing as his eyes return back to normal.

-How should I call you now? Is your name as stupid as John like last time? Humans have no taste for names.- Mocks Neuro with a sharp fanged smile, Sebastian's eyebrow twitch.

-Sebastian.

-Sounds like a dog's name.- Snickers Neuro making the other demon wish he could punch him back to hell as he turns around and starts walking, Neuro following right behind, yet before he could even open the door Pluto tackled him, of course he didn't fall but he didn't enjoy having a dog in human form all naked hugging him either.

He hated this.

-What's a hellhoud doing up here?- Asked Neuro tilting his head to the side, a frown taking hold of his face as one of his fingers held the collar around the dog's neck, hellhounds weren't suppose to be around humans, why was this one here? And this collar...

-How the hell will I know?- Snaps Sebastian as he finally pushes the damn dog off him, dog that then jumps at Neuro who pays him no mind, he seemed to be deep in thought, two fingers touching his chin as one his trademark fanged grins broke across his face.

-Interesting indeed, Luci, next time call me for I believe that that mystery must had been an exquisite one.- Sebastian just blinked at that, mystery? Where? It was just a stupid woman using the dog to scare people nothing important, though he guessed he will never understand what the likes of them saw as "exquisite mystery".

-Don't call me Luci, it's Sebastian.- Reprimanded Sebastian as he shooed Pluto off his mate before opening the door, hopefully they wouldn't meet any of the servants in their way.

-As you wish... Luci.- Bows mockingly Neuro, Sebastian sighs, was this how it felt for others to deal with him?

Their walk towards the study is spent with Sebastian swatting Neuro's hands off anything that can be picked up and the other demon himself plastering his innocent more 'human' face on, as they FINALLY get there Sebastian knocks lightly.

-Young master I'm back may I come in?- Requests Sebastian respectfully, Neuro snickers.

-So nice to see the king of hell acting like the dog he is.

-So nice to see the parrot sounding as funny as always.- Smiles Sebastian before opening the door at his master's approval, Neuro bristles at those words yet can't help but smile in approval, only bastard to level up with him after all.- Master, as requested I've brought him.- Says the butler as he closes the door behind Neuro knowing full well he wouldn't do it.

Ciel for his side blinks at it, the other demon was...

Tall.

Like, he was almost two or three inches taller than Sebastian himself, his hair was a weird mix of blonde behind and purple/brown(?) at the front with small triangle clips at the tips of his hair, eyes a sharp shade of forest green, he wore a obnoxiously bright blue suit and leather gloves.

-My you didn't say it was a little boy, they are quite rebellious now days aren't they? Humans never cease to amaze me with their lack of brain.- States Neuro as he takes on the brat's appearance, this was an altive one, he could see it with the way he held himself, and he...he could smell the potent mystery scent coming off him, a hard puzzle to solve, so delightful and such a shame he couldn't touch it.

Damn Lucifer and his stupid way of getting the best ones.

-I assume the lack of brains must be for you too since they say it takes one to know one.- Retorts Ciel, Neuro's eyes sharpen, narrowing, yet the boy for his credit don't seem to be bothered at all by his stare, this kid...

He likes him.

-Ciel Phantomhive, am I right?- Asks the parrot demon as he walks towards the desk, leaning forward as he takes one of his gloves off, he smiles at the boy's lack of fear at his monstrous hand, a claw pulling the eye patch away, the sight of the seal making him smile wider.

-Neuro the demon who eats mysteries, if you are trying to scare me it will take more than just an ugly hand and stupid smile to do it.- States Ciel flatly at the demon's closeness.

-Is that a challenge?- Asks Neuro excitedly, yet before Ciel can answer Sebastian grabs his shirt by the back of his neck, pulling him away from his master roughly, a smile not kind at all plastered on his face.

-It's not, like I said, keep yourself away from him.- Warns Sebastian like he is talking about the weather, yet his eyes are glowing that familiar ruby, black slits staring menacingly at the other, Neuro makes a mocking bow, making extra effort to appear as mocking as possible by plastering his dumb look with the oval eyes.

-As you wish your majesty.

Sebastian's eyebrow twitch at that, taking a deep breath, why was he paired with this parrot in the first place? Right, because he was the best amongst the mystery eaters, sadistic beyond words and annoying as fuck if you must.

Perfect match sadly.

-Young master, you have seen him now right? He can leave now.- States Sebastian with a tight smile, Neuro grins at that, sharp set of fangs peeking out.

-No, I wish to speak with him for a bit longer, alone.- Adds Ciel at last, smirking internally at Sebastian's annoyed look, he didn't knew this mystery eater but whoever managed to annoy Sebastian had Ciel's total likeness.

-Yes my Lord.- Sighs Sebastian giving Neuro a glare that the other returns with his 'human' innocent look and making a shooing motion with his hand, Sebastian glares even harder as he walks out, bowing at his master yet glare still on the parrot, he closed the door, he knew that despite all Neuro wouldn't touch Ciel.

Not if he valued their bond at all which he knew the other did, in fact, held dear despite the stupidity of the thought.

Ciel for his side crossed his arms over his chest as he watched the demon pull the glove on with quite the easyness despite the claws and creepiness of the hand.

-Well then boy what shall your worm brain desire to speak of with the likes of me?- Asks Neuro tilting his head to the side in question, though he perfectly knew a few things the boy was probably dying to ask, he wasn't the smartest demon in hell for nothing.

-What's with your hand and the ridiculously bright suit?- Blurts Ciel allowing his curiosity take hold of him, the demon smirks at that.

-I'm a mystery eater, I don't have the need to take the perfect form of a meaningless human to meddle in, and I'm a parrot demon, it's in my nature to be attracted to a colorful look.- States Neuro matter of fact as he starts rummaging absently through the hundred of books, not bothering to put them back as he flips a few pages before deeming it boring and reaching for another book, Ciel doesn't bother to chastise him, that would be Sebastian's problem to worry about not his.

-A parrot demon..?- Frowns Ciel instead, weren't demons just that? Demons? When he first met Sebastian a black cloud of feathers didn't allow him to see more than a silhouette from the demon and his hands were definitely normal, if you ignored the pitch black fingernails and the contract seal of course.

-Demons must roam the human world somehow in search of good food, what better than taking the form of a meaningless animal no one will bat an eye at?- States the demon like Ciel is stupid beyond words.

-Is Sebastian a bird too?- Ciel can't help but ask, because it would explain the feathers and if the demon was a bird, well, Ciel could think of a few insults to throw at him when the bastard got full of himself or mocked him.

-Not in essence seeing his actual... self but sure, he mostly takes after a crow.- Says Neuro absently as he closes a book and throws it over his shoulder with a sigh, seriously, humans became more boring through the years in literature aspects.

-His actual self?- Frowns Ciel, did making a contract changed the essence of a demon somehow? Yet the confirmation of the crow part feels like gold, oh that damn bastard wouldn't know what hit him.

-Well of course, Sebastian is it? Dog name by the way, but I guess everyone must live up to their names, he is an altive one,just like you I must say.

Ciel snorts at that, he and Sebastian alike?

Well it kind of was true but he refused to accept that fact.

Wait.

-Does he has an actual name?

-Of course he does, but I don't think humans are quite comfortable with it so he sticks to asking to be named like the dog he is.- States Neuro as he runs bored fingers across the piano's keys, eyes wandering around with a curiosity that makes Ciel for a moment wonder when was the last time the demon set foot in "the human world".

-Can I know his name?

-I don't know can you?- Asks the demon giving the boy a demonic smile.

-Can I or not?- Snaps Ciel, he did want to know Sebastian's real name, he had always been curious, because there was no way the demon held no name, that just wasn't possible.

-I don't know, are you smart boy?- Asks Neuro as he halts infront of the desk, leaning forward again, sharp malicious eyes set on annoyed sapphires, the dulled seal staring back at him almost in warning.

-I don't know are you?- Asks Ciel mildly getting annoyed at the demon's game, Neuro pressed his finger against Ciel's forehead, tapping.

-Think boy think, there are no other demons across this piece of land are they? The hellhound obeys his orders without a doubt doesn't it?

-Isn't it because he is a demon..?- Frowns Ciel not really sure what to think of those words, he never gave it too much thought to the fact of not encountering other demons, he thought that maybe demons were toxically territorial or some shit like that, and with Pluto, well, it was normal for him to obey Sebastian seeing he was a demon right?

-Hellhounds may be attracted by nature to the presence of demons but they only obey one person and one only, who do you think that may be?- Asks Neuro with his fanged smile, eyes sharp and finger still pressed on the boy's forehead.

He could feel it.

Luci was behind the door, was since the boy brought up the name thing, yet since his aura wasn't threatening Neuro didn't pay it too much mind, he knew his mate good enough to know he was definitely enjoying this as much as him.

Playing with the boy.

Ciel for his side felt his eyes go wide as realisation set upon his very soul.

-The king.- States Ciel matter of fact keeping his face as schooled as possible, he had a contract with the king of hell.

The devil himself.

Wasn't that kind of ironic?

The devil came to his aid when no one else did, he had the devil by a leash, if that wasn't hilarious he didn't knew what it was.

-Seems your brain isn't as full of worms as I thought, good for you, the king it's, no demon is allowed to set foot in this place and less much make contracts, doing so shall be seen as an act of revelry and punished with death.- States the demon looking honestly delighted at his own words.

-Can a demon die?- Asks Ciel, he doesn't know what to think of that kind of rule (?) so he chooses to ignore it, I mean, it did made sense, if you allowed one to defy you the rest would think they could get the upper hand, so better punish accordingly to give a fair warning.

-Only a demon can kill another demon.- States Neuro matter of fact as he leans away with a bored look, he wonders if Luci will let him stay around this place, not here of course but around, a lot of mysteries seem to drown the... country is it called now? They seem tastier than those from hell.

-So another demon CAN kill him?

-I didn't say that flea, no demon can beat him and if there was by any chance someone actually able to kill him, well, there's a few demons who will go after the poor bastard, me included.- Says the demon narrowing his eyes sharply, Ciel can swear on his life they just flashed neon green.

-Because he is your mate?- He can't help but ask.

-Exactly, I can't just let it pass if someone was to kill my best provider, starving isn't something I find joy in.

Interest.

Right.

So demons were really bonded by hunger, was that the only thing they lived for? To eat? Seriously?

A light knock at the door distracts him.

-Come in.

Unsurprisingly Sebastian is the one to open the door looking mildly defeated with life itself.

-Young master I'm afraid Miss Elizabeth is on her way here, I believe she will be here in less than ten minutes.- Came the flat voice, Ciel felt himself lose also some faith to live at those words as he got up.

-Well then,I believe this is where we bid our goodbyes, it was an interesting meeting.- States Ciel with a grin as he politely offers his hand, the parrot demon smiles devilishly as he grasps the boy's hand in a light handshake.

-Interesting indeed.- With that he releases Ciel's hand, and as the boy walks past the parrot demon and his butler, standing at the doorframe giving his back to them as he waits for Sebastian to follow he is able to catch by the corner of his eye the weird exchange of both demons pressing a gloved hand against the other's chest, their foreheads press together, Sebastian's eyes seem to glow after a seemingly silent quick talk, Neuro steps back, giving a bow that seems to lack the prior mocking before actually disappearing into thin air.

Ciel starts walking, feeling Sebastian as he starts following behind.

Sebastian.

Lucifer.

The King Of Hell.

God's favorite who ended up turning against him and making hundred of angels also rebel, the sinner of sinners, the devil.

-You heard us didn't you?- Ciel wasn't stupid, he knew that Sebastian when not ordered did as he pleased.

-Must I answer a question you already held the answer of my Lord?- Asks the demon with a small smirk playing at the corner of his lips, Ciel halted, turning to face the demon with a sharp look.

-Listen now, you may be the devil but I'm the boss here so don't you dare think yourself above me.- Says the boy briskly, Sebastian just blinks at that before smiling.

-Would never dream of that my Lord.

**Author's Note:**

> I'm in love with this ship I baptized as Seuro, Majin Tantei Nougami Neuro was one of my very first animes a few years ago and Kuroshitsuji following right after, kind of sad no one knows about Neuro enough to see the beautiful way he and Sebastian would match either as a couple or as friends, Inga from Un-go too though that fic is still a work in progress 🤧
> 
> And Yes I'm also in love with my theory of Sebastian being Lucifer and you can't tell me otherwise XD


End file.
